1. Field of the Invention
The present invention relates to fasteners for heat sinks, and particularly to fasteners readily and securely attaching heat sinks to electronic devices.
2. Related Art
Computer electronic devices such as central processing units (CPUs) frequently generate large amounts of heat, which can destabilize operation and cause damage. A heat sink placed in thermal contact with an electronic device mounted on a socket transfers heat from the electronic device through conduction. Oftentimes, the heat sink is secured to the electronic device with a clip.
A conventional clip comprises a spring portion and two downwardly extending legs. Each leg defines an opening. The spring portion is accommodated in a channel defined in an upper portion of a heat sink, and thereby abuts against the heat sink. The opening of each leg engagably receives a corresponding catch formed on a side of a socket, to secure the heat sink on an electronic device mounted on the socket. Contemporary high-speed CPUs are generating more and more heat. Heat sinks are accordingly being made larger and larger. As a result, conventional clips oftentimes cannot securely attach a heat sink to a CPU. The heat sink is prone to disengage or be dislodged from the CPU when it is subjected to shock or vibration during normal use.
To solve the above problem, a pair of clips is often used to secure a heat sink to an electronic device. The heat sink is secured between a pair of retention modules. The clips abut against opposite sides of a base of the heat sink. Opposite legs of each clip engage with corresponding catches formed on opposite sides of the corresponding retention module. However, using retention modules makes the system unduly complicated and costly.
Accordingly, an object of the present invention is to provide fasteners readily and securely attaching a heat sink to an electronic device.
Another object of the present invention is to provide fasteners which are pre-attached on a heat sink before the heat sink is attached to the electronic device.
To achieve the above-mentioned objects, a fastener in accordance with the present invention comprises a pin, a spring and a handle. The pin extends through a heat sink. The handle is pivotably attached to a top portion of the pin. The pin has a foot extending through a mother board and a supporting board located under the mother board to engage with the supporting board. A CPU is mounted on the mother board. The spring surrounds the pin and is located between a base of the heat sink and the handle. When the handle is rotated from a horizontal position to a vertical position, the handle compresses the spring toward the foot. The spring in turn presses the base of the heat sink against the CPU.
Other objects, advantages and novel features of the present invention will be drawn from the following detailed description of preferred embodiments of the present invention with attached drawings, in which: